尝试资源的资源范围 [英] Try-with-resources scope of resource

问题描述

在 Java 7 的 try -with-resources 构造中，我可以在 try 语句，当超出范围时，它将自动关闭。

In the try-with-resources construct of Java 7, I can declare a resource in the try statement, and it will be closed automatically when it goes out of scope.

但是，我没有找到资源范围的任何指示可用。具体来说，它可以在它被声明的try块的 catch / finally 块中提供。

However, I don't find any indication of the scope of the resource made available. Specifically, is it available in the catch/finally blocks of the try block where it is declared?

我在 Eclipse Kepler 中尝试过以下操作，但却给人一种混合的印象：

I tried the following in Eclipse Kepler, but it's giving a mixed impression:

资源变量由内容辅助（代码完成）提供：

快速修复建议更改为资源变量，但这递归地产生相同的问题它试图修复：

Quick Fix suggests changing to resource variable, but this recursively produces the same problem it's trying to fix:

我想知道正确范围限制是什么，然后在Eclipse Bug Tracker 。

I would like to know what the correct scope limitation is, before raising a bug in the Eclipse Bug Tracker.

推荐答案

此语法称为 扩展的试用资源

This syntax is called Extended try-with-resources

按< a href =http://docs.oracle.com/javase/specs/jls/se7/html/jls-14.html#jls-14.20.3> JLS ：

try ResourceSpecification
    Block
Catchesopt
Finallyopt

将被翻译成：

try {
    try ResourceSpecification
        Block
}
Catchesopt
Finallyopt

所以在您的示例中，您的资源将被限制为内部try块，因此不适用于外部 try / catch / finally 。

So, in your example, your resource will be limited to inner try block, so not available for outer try/catch/finally.

编辑：

我的问题没有嵌套的尝试块

my question does not have nested try blocks

通过在代码中明确添加catch / finally块，您将引入嵌套的try块。

By explicitly adding catch/finally block in your code, you are introducing nested try blocks.

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